Tuning for the orientation of spatial attention in dorsal premotor cortex

We tested whether neuronal activity in the dorsal premotor cortex (PMd) ref lected the orientation of selective spatial attention, as opposed to the ta rget of a reaching movement, eye position and saccade direction. These four spatial variables were dissociated in two tasks, which both required that a monkey attend to a robot's location in order to know when to make a movem ent. However, the target of the reaching movement varied; it was the robot' s location in one task, but a different location in the other task. Eye pos ition was recorded, but not explicitly controlled. Of 199 PMd neurons sampl ed, 19% had activity related to eye position, and an overlapping 11% were r elated to saccade direction (totaling 24% of the PMd sample). Of the 152 PM d neurons that lacked oculomotor relationships, approximate to 20% reflecte d the orientation of selective spatial attention. Attentional tuning may ac count, at least in part, for gaze-independent receptive fields and visuospa tial, target or goal relationships in tasks involving stimulus-response inc ompatibility.